Radiation-induced cranial tumors: clinical series and literature review

Abstract

Radiation induced tumors are well-known but rare complications of radiotherapy. Meningiomas are the most common radiation-induced (RI) cranial tumors, followed by gliomas and sarcomas, while other tumors as haemangioblastomas remain extremely exceptional. We present 7 patients with RI brain tumors diagnosed and treated at our institution between 1990 and 2006. Retrospective review of their clinical charts is supplied. All patients were irradiated during childhood as a treatment for another disease, and fulfilled the criteria of RI neoplasia. Four patients developed meningiomas and three developed other tumors (one glioblastoma, one softtissue sarcoma and one hemangioblastoma). In all cases a complete surgical removal was achieved. Preoperative assessment based on MRI supplied the correct diagnosis in six patients. The most important risks factors described in the literature for developing RI tumors are the age at which radiotherapy was administered and the dose of radiation applied. Differential diagnosis of RI tumors includes any tumor appearing after radiotheraphy, especially recurrences of the primary disease, as RI neoplasias are a rare complication. Even in cases with complete surgical resection, prognosis of this clinical entity is basically related to the histology of the RI tumor.